Gingivitis and periodontitis: the first is reversible, the second is not, and the difference is bone

Gingivitis and periodontitis are often presented as two stages of one process, as though the former inevitably led to the latter. Reality is more nuanced and the distinction has practical consequences.

Gingivitis is inflammation of the soft tissues without attachment loss. Once the cause is removed, the tissue returns to its previous condition: it is reversible in the full sense.

Periodontitis entails loss of attachment and supporting bone. That tissue does not spontaneously reform, and therapy arrests progression without restoring what has been lost.

The difference is measured rather than estimated. Probing is required, as is knowing the position of the cemento-enamel junction: a deep pocket may be a false pocket from oedema in severe gingivitis.

What surprises many is that not every gingivitis progresses to periodontitis. Individual susceptibility, largely genetic, determines who will progress and who will live with gingivitis for years.

This does not make gingivitis harmless: it means it is a condition to be treated in its own right, and that its persistence is the necessary but not sufficient precondition for periodontitis.

The signs pointing towards transition are persistent bleeding despite correct hygiene, the appearance of true pockets, early mobility and tooth migration.

The patient reporting that their teeth are shifting or that a space has appeared between the incisors is describing a sign of lost support, not an aesthetic matter.

A radiograph is necessary to assess bone, and the absence of recent radiographs in a patient with generalised bleeding is a diagnostic gap rather than caution.

Communication with the patient changes with the diagnosis. In gingivitis the message is one of full recovery, and that motivates; in periodontitis it is arrest and maintenance, and promising recovery creates expectations that will be disappointed.

Telling a periodontal patient that hygiene appointments will return things to how they were is a communication error paid for in later years, when the patient attributes to therapy a failure that never occurred.

Smoking and uncontrolled diabetes are the two factors that most shift the probability of transition, and they are addressed as part of the therapy rather than as generic advice.

In summary: gingivitis is reversible and periodontitis is not, the difference is measured by probing and radiography, not every gingivitis progresses, the signs of transition are recognisable, and communication is calibrated to the diagnosis.